ExpressionFunction.php

<?php

/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier <fabien@symfony.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Gismo\Component\ExpressionLanguage;

/**
 * Represents a function that can be used in an expression.
 *
 * A function is defined by two PHP callables. The callables are used
 * by the language to compile and/or evaluate the function.
 *
 * The "compiler" function is used at compilation time and must return a
 * PHP representation of the function call (it receives the function
 * arguments as arguments).
 *
 * The "evaluator" function is used for expression evaluation and must return
 * the value of the function call based on the values defined for the
 * expression (it receives the values as a first argument and the function
 * arguments as remaining arguments).
 *
 * @author Fabien Potencier <fabien@symfony.com>
 */
class ExpressionFunction
{
    private $name;
    private $compiler;
    private $evaluator;

    /**
     * Constructor.
     *
     * @param string   $name      The function name
     * @param callable $compiler  A callable able to compile the function
     * @param callable $evaluator A callable able to evaluate the function
     */
    public function __construct($name, callable $compiler, callable $evaluator)
    {
        $this->name = $name;
        $this->compiler = $compiler;
        $this->evaluator = $evaluator;
    }

    public function getName()
    {
        return $this->name;
    }

    public function getCompiler()
    {
        return $this->compiler;
    }

    public function getEvaluator()
    {
        return $this->evaluator;
    }
}